Many functions of modern devices in automotive, consumer and industrial applications, such as converting electrical energy and driving an electric motor or an electric machine, rely on power semiconductor devices. For example, Insulated Gate Bipolar Transistors (IGBTs). Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) and diodes, to name a few, have been used for various applications including, but not limited to switches in power supplies and power converters.
A power semiconductor device usually comprises a semiconductor body configured to conduct a load current along a load current path between two load terminals of the device. Further, the load current path may be controlled by means of an insulated electrode, sometimes referred to as gate electrode. For example, upon receiving a corresponding control signal from, e.g., a driver unit, the control electrode may set the power semiconductor device in one of a conducting state and a blocking state.
Further, for conducting the load current, the power semiconductor device may comprise one or more power cells which may be arranged in a so-called active region of the power semiconductor device. The power semiconductor device may be laterally confined by a chip edge, and between the chip edge and the active region that comprises the one or more power cells, there may be arranged a termination structure.
In terms of power semiconductor devices, such a termination structure is also referred to as a “high voltage termination structure”, and it may serve the purpose of influencing the course of the electric field within the semiconductor body, e.g., so as to ensure reliable blocking capability of the power semiconductor device. To this end, the termination structure may comprise one or more components arranged within the semiconductor body, and also one or more components arranged above a surface of the semiconductor body.
For example, a termination structure may comprise an ohmic layer that connects the electrical potential of the first load terminal with the electrical potential of the second load terminal. For example, this may allow for symmetrizing an electric field, at least within that section of the semiconductor body that forms a part of the termination structure.